Flat panel displays, such as LCD and plasma television, have become increasingly popular and now almost dominate the market which used to belong to the traditional CRT. Because flat panel displays are thin in profile, they are often mounted on walls, brackets or other vertical flat surfaces in order to save space. For a better viewing angle, flat panel displays are often mounted on a support device which can be rotated to a desired angle. Numerous patents directed to mounting devices having function of adjustable viewing angle can be found.
Some prior art, such as U.S. Pat. No. 7,063,295 (Gil Soon Kwon), U.S. Pat. No. 6,402,109 (Jay Dittmer), U.S. Pat. No. 6,554,242 (Sang Wook Kim), is directed to mounting devices having mechanisms which enable them to be rotated about a horizontal axis and thus the angle to their mounting surface can be adjusted.
Some prior art, such as U.S. Pat. No. 6,905,101 (Jay Dittmer), U.S. Pat. No. 6,102,348 (Edward L. O'Neill), WO 2006/014051 (Mock, Dae Gwan), discloses mounting devices having mechanisms which enable them to be rotated about a vertical axis and thus the angle to their mounting surface can be adjusted. U.S. Pat. No. 6,905,101 further includes a mechanism which enables the mounting device disclosed therein to also be rotated about a horizontal axis and thus the angle to its mounting surface can be adjusted.
It is noted that the mechanisms shown in the above patents are generally in the form of links or arms. The links or arms have the advantage of simple structure, but are weak or too large, when they are used to support an object having substantial weight, particularly if they are required to be rotatable. Furthermore, as the display panel gets larger and heavier, the structure of a support device formed of links or arms can be too weak to safely support a heavy flat panel display.
Furthermore, when the angle of a display is adjusted, the center of gravity of the device as disclosed above along with the display will be displaced away from the wall or the surface where the device/display is mounted, and the displacement will impose additional burden on the support device, especially in translational movement, aggravating the problem of structural weakness of the support device.